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PL
Praca przedstawia zagadnienie dotyczące pomiaru i analizy zużycia energii w trakcie cyklu wiercenia termicznego. Przedstawiono oparte na tokarce CNC stanowisko badawcze, którego elementem wyposażenia był eksperymentalny układ poboru energii oparty o licznik energii elektrycznej oraz siłomierz. Zastosowane urządzenia pomiarowe pozwalały na rejestrację obciążenia sieci energetycznej, obciążenia napędów obrabiarki, siłę osiową, moment hamujący wiertło, aktualne obroty wrzeciona obrabiarki, pozycję wiertła względem obrabianego materiału i wartości rejestrów parametrów pomocniczych w strategii adaptacyjnego sterowania posuwem. Rozważano dwa przypadki cyklu wiercenia: wykonanie pojedynczego otworu oraz wykonanie szeregu otworów w jednym cyklu. Testowano pięć strategii sterowania posuwem w trakcie cyklu wiercenia, w tym adaptacyjne sterowanie posuwem i rekurencyjną metodę optymalizacji posuwu. Dla porównania wykonano także otwory tradycyjnymi wiertłami krętymi HSS. Na podstawie uzyskanych rezultatów badań można stwierdzić, że metoda wiercenia ciernego może być zaliczona do energooszczędnych metod wykonywania otworów w elementach cienkościennych.
EN
The work presents the issue of measuring and analyzing energy consumption during a thermal drilling cycle. A research stand based on a CNC lathe was presented, the equipment of which was an experimental energy consumption system based on an electricity meter and a force gauge. The measuring devices used allowed for recording the load on the power grid, the load on the machine tool drives, the axial force, the drill braking torque, the current rotation of the machine tool spindle, the position of the drill in relation to the workpiece and the values of auxiliary parameter registers in the strategy of adaptive feed control. Two cases of a drilling cycle were considered: making a single hole and making a series of holes in one cycle. Five feed control strategies were tested during the drilling cycle, including adaptive feed control and a recursive feed optimization method. For comparison, holes were also made with traditional HSS twist drills. Based on the obtained test results, it can be concluded that the friction drilling method can be included in the energy-saving methods of making holes in thin-walled elements.
EN
The paper introduces Extended Identification-Based Predictive Control (EIPC), which is a novel control method developed for the problem of adaptive impact mitigation. The model-based approach utilizing the paradigm of Model Predictive Control is combined with sequential identification of selected system parameters and process disturbances. The elaborated method is implemented in the shock-absorber control system and tested under impact loading conditions. The presented numerical study proves the successful and efficient adaptation of the absorber to unknown excitation conditions as well as to unknown force and leakage disturbances appearing during the process. The EIPC is used for both semi-active and active control of the impact mitigation process, which are compared in detail. In addition, the influence of selected control parameters and disturbance identification on the efficiency of the impact absorption process is assessed. As a result, it can be concluded that an efficient and robust control method was developed and successfully applied to the problem of adaptive impact mitigation.
EN
Reliability and safety of an electro-hydraulic position servo system (EHPSS) can be greatly reduced for potential sensor and actuator faults. This paper proposes a novel reconfiguration control (RC) scheme that combines multi-model and adaptive control to compensate for the adverse effects. Such a design includes several fixed models, one adaptive model, and one reinitialized adaptive model. Each of the models has its own independent controller that is based on a complete parametrization of the corresponding fault. A proper switching mechanism is set up to select the most appropriate controller to control the current plant. The system output can track the reference model asymptotically using the proposed method. Simulation results validate robustness and effectiveness of the proposed scheme. The main contribution is a reconfiguration control method that can handle component faults and maintain the acceptable performance of the EHPSS.
EN
The paper presents an adaptive control algorithm for an asymmetric quadcopter. For determining the control algorithm, the identification was made, and an identification algorithm is presented in the form of a recursive method. The control method is realized using inverse dynamics, full state feedback and finally adaptive control method. The algorithms for the off-line and on-line identification of quadcopter model parameters are also presented. The paper shows the effectiveness of the selected algorithm on the example of the movement along a given trajectory. Finally, recommendations of the application of these different methods are made.
PL
W pracy przedstawiono algorytm sterowania adaptacyjnego dla asymetrycznego quadrocoptera. W celu określenia sterowania zrealizowano identyfikację parametrów i przedstawiono algorytm identyfikacji w formie metody rekurencyjnej. Metoda sterowania realizowana jest z wykorzystaniem dynamiki odwrotnej, przesuwania biegunów oraz sterowania adaptacyjnego. Zaprezentowano algorytmy identyfikacji parametrów modelu quadrocoptera w trybie off-line i on-line. W artykule przedstawiono skuteczność wybranych algorytmów na przykładzie ruchu wzdłuż podanej trajektorii. Na zakończenie artykułu przedstawiono zalecenia dotyczące stosowania różnych metod sterowania.
EN
To solve the nonlinear control problems of the unknown time-varying environmental disturbances and parametric uncertainties for ship course-keeping control, this paper presents an adaptive self-regulation PID (APID) scheme which can ensure the boundedness of all signals in the ship course-keeping control system by using the Lyapunov direct method. Compared with the traditional PID control scheme, the APID control scheme not only is independent of the model parameters and the unknown input, but also can regulate the gain of PID adaptively and resist time-varying disturbances well. Simulation results illustrate the effectiveness and the robustness of the proposed control scheme.
EN
In this paper, the issue related to control of the plant with nonconstant parameters is addressed. In order to assure the unchanged response of the system, an adaptive state feedback speed controller for permanent magnet synchronous motor is proposed. The model-reference adaptive system is applied while the Widrow-Hoff rule is used as adjustment mechanism of controller’s coefficients. Necessary modifications related to construction of the cost function and formulas responsible for adjustment of state feedback speed controller’s coefficients are depicted. The impact of adaptation gain, which is the only parameter in proposed adjustment mechanism, on system behaviour is experimentally examined. The discussion about computational resources consumption of the proposed adaptation algorithm and implementation issues is included. The proposed approach is utilized in numerous experimental tests on modern SiC based drive with nonconstant moment of inertia. Comparison between adaptive and nonadaptive control schemes is also shown.
EN
The paper describes a nonlinear controller design technique applied to a servo drive in the presence of hard state constraints. The approach presented is based on nonlinear state-space transformation and adaptive backstepping. It allows us to impose hard constraints on the state variables directly and to achieve asymptotic tracking of any reference trajectory inside the constraints, despite unknown plant parameters. Two control schemes (with and without integral action) are derived, investigated and then compared. Several examples demonstrate the main features of the design procedure and prove that it may be applied in case of motion control problems in electric drive automation.
EN
The paper presents a method for designing a neural speed controller with use of Reinforcement Learning method. The controlled object is an electric drive with a synchronous motor with permanent magnets, having a complex mechanical structure and changeable parameters. Several research cases of the control system with a neural controller are presented, focusing on the change of object parameters. Also, the influence of the system critic behaviour is researched, where the critic is a function of control error and energy cost. It ensures long term performance stability without the need of switching off the adaptation algorithm. Numerous simulation tests were carried out and confirmed on a real stand.
EN
This paper deals with two control algorithms which utilize learning of their models’ parameters. An adaptive and artificial neural network control techniques are described and compared. Both control algorithms are implemented in MATLAB and Simulink environment, and they are used in the simulation of a postion control of the LWR 4+ manipulator subjected to unknown disturbances. The results, showing the better performance of the artificial neural network controller, are shown. Advantages and disadvantages of both controllers are discussed. The usefulness of the learning algorithms for the control of LWR 4+ robots is discussed. Preliminary experiments dealing with dynamic properties of the two LWR 4+ robots are reported.
EN
Stabilization of the carbon monoxide (CO) in the waste gas is a common technical problem in many industrial plants. Stabilization can be performed continuously by regulating the fuel input or by regulating the exhaust gas draught. This paper proposes an adaptive control system for CO stabilization in waste gases based on a discrete controller. Heuristic adaptation of a discrete controller is based on continuous optimization of controller parameters. The advantage of this solution is that the control system does not need to perform the identification of the controlled system repeatedly. The parameters of the controller are dynamically optimized during the production process. By regulating the under-pressure, we change the amount of air supplied to the combustion chambers, which affects the combustion of gaseous fuel and also the concentration of CO in the waste flue gas. The control algorithm was verified for the combustion process in coke making. The proposed control achieved good stabilization quality when verified in simulation and also in an industry operation. The CO level at which the waste gas temperature was highest was selected as the setpoint. It was found that the stabilization of CO in waste gas to lower values is possible to achieve higher waste gas temperature and by that, higher temperatures in heating chambers.
EN
This paper analyses the management process of the vessel traffic control on one-way section on navigable canal with the adaptive time-sequential filter (traffic lights). One-way section on canal significantly decreases waterway capacity and requests special attention in control and regulation of the vessel traffic. The vessel traffic is a stochastic variable, and the vessel traffic control needs to be flexible and adaptive in order to achieve the required traffic flow with minimal delays. On the one-way section, two independent variable vessel flows from opposite directions are encountered, and fixed (predefined) signal plans lead to an increase in vessel delays. An appropriate solution is development of a Fuzzy Control System (FCS) for the vessel traffic control. A control algorithm is designed according to a set of linguistic rules that describes input parameters for the control strategy. The estimated and approximate input parameters are implemented in the algorithm as fuzzy sets. The final result of the developed algorithm is the traffic light scheme (duration of green light for certain direction). The presented control system can be used as an adaptive automatic control system for the vessel traffic control processes on navigable canals or on critical sections of other waterways.
EN
Today's highly automated manufacturing specifies the service time of a tool in a way that the tooling costs are balanced against the potential costs of a tool failure. However, the potential cost induced by a tool malfunctioning are rather high. Therefore, the current state-of-the art tackles this issue by replacing the tools prematurely at fixed intervals. To tap into the potential of under-utilized tool runtime this work purposes the use of sensory-tool holders and an interfering feedback loop to the machine tool control system. Besides its real-time closed loop control, to avoid tool failure, it also provides data in the context of (a) the work order, (b) the produced part, (c) the NC-block and command line, on (d) specific machines. Based on this data an ex-post analysis to optimize tool-life and productivity scenarios becomes possible, e.g. custom NC-programs for certain work-orders, configurations and machines. Furthermore, downstreamed work steps can be changed e.g. only to measure produced workpieces if abnormal vibrations are reported by in-process-monitoring.
EN
The issue addressed in the article concerns the current needs and possibilities of computer-aided design of adaptive control strategies in machining processes. A simulative method of selecting the adaptive feed control strategy while rough turning materials difficult to machine, effective and inexpensive in its implementation, based on controlling the load placed on the machine's drives, has been presented. The results of a number of virtual tests of the proposed feed control strategy have been included, while paying particular attention to the stability of the machining process during moments of sudden change in the machining allowance. The obtained results meet the accepted quality indicators of the control algorithm. At the same time, the experiences collected by the author while conducting the tests confirmed the complexity of the issue and the resulting necessity to implement a comprehensive simulation testing program.
EN
We introduce a control strategy to solve the regulation control problem, from the perspective of trajectory planning, for an uncertain 3D overhead crane. The proposed solution was developed based on an adaptive control approach that takes advantage of the passivity properties found in this kind of systems. We use a trajectory planning approach to preserve the accelerations and velocities inside of realistic ranges, to maintaining the payload movements as close as possible to the origin. To this end, we carefully chose a suitable S-curve based on the Bezier spline, which allows us to efficiently handle the load translation problem, considerably reducing the load oscillations. To perform the convergence analysis, we applied the traditional Lyapunov theory, together with Barbalat’s lemma. We assess the effectiveness of our control strategy with convincing numerical simulations.
EN
Torsional vibrations induced in drilling systems are detrimental to the condition of the machine and to the effectiveness of the engineering process. The cause of vibrations is a nonlinear and unknown friction between a drill string and the environment, containing jumps in its characteristics. Nonlinear behaviour of the friction coefficient results in self-excited vibration and causes undesirable stick-slip oscillations. The aim of this paper is to present a novel adaptive technique of controlling vibrating systems. The scheme is based on the linear quadratic regulator and uses direct measurements of the friction torque to synthesize its linear dynamic approximation. This approach allows generating a control law that takes into account the impact of the friction on the system dynamics and optimally steers the system to the desired trajectory. The controller’s performance is examined via numerical simulations of the stabilization of the drilling system. The proposed solution outperforms the comparative LQG regulator in terms of the minimization of the assumed cost functional and the overall stability of the control system under the nonlinear disturbance.
EN
The genesis of both coherent structures and reactive flow control strategies is explored. Futuristic control systems that utilize microsensors and microactuators together with artificial intelligence to target specific coherent structures in a transitional or turbulent flow are considered. Of possible interest to the readers of this journal is the concept of smart wings, to be briefly discussed early in the article.
EN
This work describes a new study to achieve a combination of modified function projective synchronization between three different chaotic systems through adaptive control. Using the Lyapunov function theory, the asymptotic stability of the error dynamics is obtained and discussed. Further, we set some appropriate initial conditions for the state variables and assigning specific values to the parameters and obtain the graphical results, which shows the efficiencies of the new method. Finally, we summarized our work with conclusion and references.
EN
We study an elegant snap system with only one nonlinear term, which is a quadratic nonlinearity. The snap system displays chaotic attractors, which are controlled easily by changing a system parameter. By using analysis, simulations and a real circuit, the dynamics of such a snap system has been investigated. We also investigate backstepping based adaptive control schemes for the new snap system with unknown parameters.
EN
Passive noise reduction methods require thick and heavy barriers to be effective for low frequencies and those clasical ones are thus not suitable for reduction of low frequency noise generated by devices. Active noise-cancelling casings, where casing walls vibrations are actively controlled, are an interesting alternative that can provide much higher low-frequency noise reduction. Such systems, compared to classical ANC systems, can provide not only local, but also global noise reduction, which is highly expected for most applications. For effective control of casing vibrations a large number of actuators is required. Additionally, a high number of error sensors, usually microphones that measure noise emission from the device, is also required. All actuators have an effect on all error sensors, and the control system must take into account all paths, from each actuator to each error sensor. The Multiple Error FXLMS has very high computational requirements. To reduce it a Switched-Error FXLMS, where only one error signal is used at the given time, have been proposed. This, however, significantly reduces convergence rate. In this paper an algorithm that uses multiple errors at once, but not all, is proposed. The performance of various algorithm variants is compared using simulations with the models obtained from real active-noise cancelling casing.
EN
The paper describes an adaptive control system of the waves, implemented in the Ship Design and Research Centre, CTO S.A. The purpose of generating the waves in the towing tank is the modelling of the environmental conditions during hydrodynamic model tests. The tests are performed on scale models of towed or free running ships, anchored structures like oil rigs or bottommounted structures, e.g. wind turbines. In the towing tank of CTO S.A., the waves are generated using a flap-type wavemaker with hydraulic drive. The adaptive control system includes gain scheduling and Black-Box model. It has been developed and implemented using the 32-bit embedded system and computer application (C#.NET). The Black-Box model was proposed as a simple solution allowing compensating the hydromechanical phenomena affecting the generated waves, i.e. disintegration, reflection, damping and nonlinear energy transfer. The solution proved to be sufficient to generate required wave spectra with expected accuracy in a user-friendly manner.
PL
Artykuł opisuje adaptacyjny system sterowania falami basenowymi, który został wdrożony w Centrum Techniki Okrętowej (CTO) S.A. Fale są generowane w głębokowodnym basenie holowniczym podczas testów modelowych w celu odwzorowania warunków oddziaływania środowiska morskiego. Testy są przeprowadzane na modelach holowanych lub pływających swobodnie (statki), zakotwiczonych (platformy) lub przymocowanych trwale do dna (turbiny wiatrowe). W głębokowodnym basenie holowniczym CTO S.A., fale generowane są przez płytowy wywoływacz fal z płytą mocowaną powyżej dna basenu i z napędem hydraulicznym. Adaptacyjne sterowanie falą basenową obejmuje harmonogramowanie wzmocnienia i model typu Black-Box. Opracowany system sterowania został implementowany w 32-bitowym systemie wbudowanym i aplikacji komputerowej w języku C# w środowisku .NET. Wprowadzony model typu Black-Box uwzględnia efekty hydromechanicznych procesów i zjawisk – m. in. rozpadu, odbicia, tłumienia i nieliniowego transferu energii – które mają wpływ na generowane fale. Przedstawione rozwiązanie pozwala w prosty sposób i z oczekiwaną dokładnością modelować zadane widma fal basenowych.
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